Recently, as environmental problems are on the rise around the world, methods of reducing fuel consumption to cope with these problems are developed in a whole range of industries. In order to reduce fuel consumption, solutions proposed in the automobile industry include improvement of efficiency of a vehicle engine and weight reduction of a vehicle. Vehicle weight reduction is one of good measures to increase fuel efficiency of a vehicle. However, the vehicle weight reduction may cause problems, such as a difficulty in satisfying strength and durability requirements of vehicles. Therefore, addressing of these problems is the most important goal in the automobile industry.
Accordingly, due to the environmentally-friendly trends, the automobile industry have developed various eco-friendly vehicles while aiming for reduction of the carbon dioxide emission amount to 95 g/km, corresponding to 27% of the current carbon dioxide emission amount, up to 2021 on the basis of European regulations. Further, in order to satisfy a U.S. Corporate Average Fuel Economy (CAFE) regulation value in 2025, i.e., 54.5 mpg (23.2 km/l), automakers strive to develop downsizing technologies and fuel efficiency improvement technologies.
Further, the use of materials in consideration of the environments has been required in the automobile industry, and in order to meet the requirements for preventing environmental pollution, various research and development of eco-friendly and lightweight materials, for example, natural fibers, bio-plastics, lightweight materials, etc., have been carried out.
Accordingly, a natural fiber reinforced board has been manufactured by forming a felt layer by needle-punching natural fiber and chemical fiber and is molded into a vehicle interior part through heat pressing using a flat plate and cold press molding. However, such a natural fiber reinforced board has limited weight reduction effects and requires additional pose-processing, thus excessively raising manufacturing costs.
The present disclosure has been developed, in view of the above problems, to provide a natural composite material multilayer structure and a method of manufacturing the same.